1. Field of the Invention
The present invention relates to, for example, an information storage medium called an IC card and having a built-in IC (Integrated Circuit) chip with a nonvolatile data memory and a control element such as CPU. Moreover, the present invention relates to a medium processing system composed of such an information storage medium and a medium processing device called a reader/writer and which records data in the information storage medium and which reads data stored in the information storage medium.
2. Description of the Related Art
In recent years, secure IC cards (contact type and non-contact type) have been prevailing remarkably. These IC cards have a nonvolatile memory that can hold data even when power supply is cut off, a communication I/F that can communicate with a reader/writer, a control element such as CPU which performs various operations, ROM that stores operation programs for CPU, and RAM that temporarily stores data.
ISO/IEC7816-4 specifies the concept of EF (Elementary File) as a data structure for accesses via commands. A record type structure, a linear structure, and a cyclic structure have been defined for EF.
ISO/IEC7816-4(2005) has a new additional concept of EF for a data object structure. That is, ISO/IEC7816-4(2005) has the additional basic concept of a data object structure composed of several data of a TVL data structure composed of a tag section, a length section, and a value section. The tag section describes a tag (identification information) indicating the type of data. The length section stores the data length of the data stored in the value section. The value section stores the process target data (write or read data). A data object is normally retrieved by specifying the value of the tag.
For example, a technique for the retrieval of a data object is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2004-178101. A summary of the technique disclosed in Jpn. Pat. Appln. KOKAI Publication No. 2004-178101 is provided below. An IC card reader reads a file recorded in a recording section of an IC card through communication with a main control section. The IC card reader registers a repetitive read execution command in association with registration numbers. To read information in which the position of data to be read is unspecified, from the IC card, the IC card reader receives, from the main control section, an interpreter execution command including a registration number and specification information to be searched for. The IC card reader uses the registered read execution command to search for a data object in an IC card file having the specification information. The IC card reader then returns the data object to the main control section as an interpreter execution response.